Torture prosecutions in the near future?

Does Eric Holder's statement mean he's going to prosecute Bush Administration figures for torture?

Eric Posner, writing at the Volokh Conspiracy, doesn't think so. Among other reasons:

3. There are other more mundane reasons that will allow Justice Department officials to persuade themselves not to investigate and/or prosecute that are not connected to politics. Prosecutors prosecute when they believe that they will win. To do otherwise is to waste public resources that could be used to put people in jail. Any experienced prosecutor would engage in the following train of reasoning (even putting aside the immunity provisions in the Military Commissions Act). The waterboarders themselves will testify that they received assurances from superiors and lawyers that waterboarding is not illegal, and that they believed that waterboarding was necessary to protect the nation. The superiors, up to Bush himself, will testify that lawyers assured them that waterboarding is not illegal, and that they believed that waterboarding was necessary to protect the nation. The lawyers will testify that they honestly believed that waterboarding is not torture—it caused “pain” but not “severe pain,” in the language of the statute—and that in any event statutes need to be interpreted narrowly to avoid a conflict with the president’s commander-in-chief powers. The jury will believe all these people and it will refuse to convict or, at best, it will hang, prolonging everyone’s agony. It might refuse to convict because it doesn’t believe that anyone has the requisite mens rea; because it doesn’t understand the law; or because (most likely) it just doesn’t believe that people should go to jail when they are trying to protect the nation and the law in question is confusing or ambiguous.

4. Back to politics. One can easily imagine the defense strategy, which will start by calling to the stand various Democratic senators and representatives who had been informed of the interrogation tactics and did not publicly object to them at the time. The testimony would surely be entertaining, as the politicians would be put in the impossible position of either admitting their moral complicity, which would make the entire trial look like a political show trial designed to punish Republicans but not Democrats, or looking like cowards who knew that the government was breaking the law but despite their oath to the Constitution were unwilling to do anything about it. Do Obama and Holder really want to put leaders of their own party in Congress in this position?

5. Finally, just what is Holder’s position on these issues? Has he really committed himself to anything? What about the all-important issue of executive power (I’ve added emphasis to certain sentences in the transcript excerpts below)?
....
HATCH: That still doesn't negate the fact that the president may have inherent powers under Article 2 that even a statute cannot vary.

HOLDER: Well, sure. The...

HATCH: Do you agree with that statement?

HOLDER: Yes, there are certain things that the president has the constitutional right, authority to do, that the legislative branch cannot impinge upon.
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Holder himself can’t dispute the central premise of the Bush DOJ’s war-on-terror memos; at best, he can say that (in his words) “There’s always the tension in trying to decide where that balance is struck” when the president’s and Congress’ constitutional powers conflict, and that he would have struck it differently. A jury will convict on that basis?